Linked Life Data

1324708

Source:http://linkedlifedata.com/resource/pubmed/id/1324708

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
32
pubmed:dateCreated
1992-9-29
pubmed:abstractText
The de novo design and synthesis of ruthenium-labeled cytochrome b5 that is optimized for the measurement of intracomplex electron transfer to cytochrome c are described. A single cysteine was substituted for Thr-65 of rat liver cytochrome b5 by recombinant DNA techniques [Stayton, P. S., Fisher, M. T., & Sligar, S. G. (1988) J. Biol. Chem. 263, 13544-13548]. The single sulfhydryl group on T65C cytochrome b5 was then labeled with [4-(bromomethyl)-4'-methylbipyridine] (bisbipyridine)ruthenium2+ to form Ru-65-cyt b5. The ruthenium group at Cys-65 is only 12 A from the heme group of cytochrome b5 but is not located at the binding site for cytochrome c. Laser excitation of the complex between Ru-65-cyt b5 and cytochrome c results in electron transfer from the excited state Ru(II*) to the heme group of Ru-65-cyt b5 with a rate constant greater than 10(6) s-1. Subsequent electron transfer from the heme group of Ru-65-cyt b5 to the heme group of cytochrome c is biphasic, with a fast-phase rate constant of (4 +/- 1) x 10(5) s-1 and a slow-phase rate constant of (3 +/- 1) x 10(4) s-1. This suggests that the complex can assume two different conformations with different electron-transfer properties. The reaction becomes monophasic and the rate constant decreases as the ionic strength is increased, indicating dissociation of the complex.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7237-42
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Genetic engineering of redox donor sites: measurement of intracomplex electron transfer between ruthenium-65-cytochrome b5 and cytochrome c.
pubmed:affiliation
Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville 72701.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.